use suspend function inside lambda of `open` method

[doyaaaaaken]

In the below code, a compile error happen because suspend function cannot be called inside lambda of open function.
So make it callable.

suspend fun processRow(row: List<String>): List<String> {
    return row.map { "prefix-$it" }
}

val rows: List<List<String>> = csvReader().open("test.csv") {
    readAllAsSequence()
        .map { row -> processRow(row) } // Compile ERROR!! processRow is suspend function so cannot call inside lambda
        .toList()
}

Discusssion: https://kotlinlang.slack.com/archives/CMAL3470A/p1601651001001000

[doyaaaaaken]

released at v0.13.0